This invention relates to a stopper structure and stopper member for preventing a grommet from coming off from a panel.
Generally, a grommet is integrally made from elastic material such as a rubber and formed with a fitting portion, on one side, to be fit in a through hole of a panel. The grommet is formed with an inserting portion for receiving a wire on the other side. The grommet is further formed with a stopper flange on an end of the fitting portion and the stopper flange has an outside diameter larger than the inside diameter of the through hole.
When mounting the grommet on the panel, the grommet is inserted Into the through hole of the panel from one side to the other side fitting the fitting portion in the through hole. Thus, the grommet is prevented from coming off from the through hole because the flange engages the inner peripheral edge of the through hole when a tension force is exerted to the grommet on the inserting portion side.
However, because the stopper flange is made from elastic material, when, for example, an oblique tension force is exerted to the grommet, the stopper flange is apt to be deformed resulting in the grommet coming off from the panel.
Therefore, to solve such a problem, the stopper flange is formed thickly, and alternately the stopper flange is formed with an annular groove at the internal circumference of the flange and a ring made of rigid material is fit into the annular groove (refer to Japanese Utility Model Laid Open No. 1-130230).
However, when making the stopper flange thick, processing costs and the weight of the grommet are increased. When forming the annular groove at the internal circumference of the flange and fitting the rigid ring into the annular groove, it is troublesome to mount and demount the ring, so that the operability when mounting and demounting the ring is poor.